1. Field of the Invention
The present invention relates to a device and a method for a traffic flow assistant for a vehicle, including a surroundings sensor system which recognizes traffic-relevant objects on a traffic lane on which the vehicle is traveling and on at least one further adjacent lane, gaps in the traffic being recognized with the aid of the surroundings sensor system and vehicle-dynamic parameters of the objects being determined and future gaps in the flow of traffic being able to be predicted therefrom. For these recognized gaps and predicted gaps, lane change options are ascertained and, from this and the present and/or predicted presence of gaps in the traffic suitable for changing lanes and the vehicle-dynamic state of the vehicle, a signal for the lane selection is generated, which is dependent on the lane change options and an optimization strategy.
2. Description of the Related Art
Many drivers of vehicles find it difficult to select a favorable point in time for changing lanes on multilane roadways. In particular changing from the right lane into the faster traffic of the left lane is considered to be hazardous, since inexperienced drivers often find it difficult to estimate relative speeds in relation to other vehicles, i.e., to predict how rapidly another vehicle is approaching. A person is generally only capable of this by observing how rapidly another vehicle becomes “larger.” For rearward vehicles, however, this means a longer look in the mirror, which may distract from the driving situation ahead of the host vehicle.
However, sensors such as radar systems or video systems are capable of measuring the relative speed of an object rapidly and precisely, in addition to the distance.
Systems which relate to a simple lane change assistant are already known and relate to a warning system, which warns in case of a recognized hazard situation. In particular, they warn if the driver intends a driving maneuver which creates a hazardous situation.
Published German patent document DE 43 13 568 C1 describes a system for measuring and determining gaps which allow a traffic lane change. It also considers driving speed changes of the host vehicle, to achieve these gaps. However, the method is only initiated when the driver manually operates a travel direction change indicator lever (turn signal). In addition, if the look-ahead monitoring establishes a slower object ahead of the vehicle, a request to operate this travel direction change indicator lever may take place.
Published German patent application document DE 10 2007 007 507 A1 also describes a “gap warning device,” which determines when a gap is free on the adjacent lane to communicate this to the driver. He/she is optionally also given driving instructions (braking, accelerating, waiting until after the next vehicle). For this purpose, the speeds and acceleration or deceleration possibilities are considered. However, the accelerations of the other vehicles are not ascertained, but rather only a history of one's own acceleration behavior is used to obtain suggestions for the acceleration capability. Driving suggestions are only to be output with the aid of a dialogue unit if the behavior of the driver indicates such a lane change intention.
However, a system which outputs autonomous lane change recommendations, which are not necessarily in conjunction with a driver intention, is not known.